Hi Ute,
If you are still having this problem, then I recommend you use the Can Discover permission. Can Discover allows the designated Identities to see the items inside of a table or in a relationship of another item, but it does not allow you to open the item because that ability is given with the Can View permission. Therefore, I would create an Identity that would act as a group of people who can see the myDoc items, and only assign the Can View permission to that group.
Andrew
Andrew Johnson
Software Engineer for Aras Labs